Mosaic Martial Arts Assassin D2R Build

Introduction

Welcome to the comprehensive D2R Guide for the Mosaic Assassin. This guide will cover all the essential information you need to know to become a skilled Mosaic Assassin, a new and powerful build enabled by the weapon runeword Mosaic in D2R 2.6. As a beginner, this guide will help you understand the class's skills, stat allocation, gear options, leveling strategies, and endgame content. Follow the guide, and you'll be on your way to becoming one of the most viable, fastest clearing characters in the game, capable of tackling any area in Hell, including Ubers and Dclone.

The Mosaic Runeword (Mal + Gul + Amn in a 3 socket Claw base)

+ 2 to Martial Arts Skills

20% Increased Attack Speed

200 - 250 Enhanced Damage

20% Bonus to Attack Rating

3-14 Cold Damage

Prevent Monster Heal

*25% chance not to consume charges on striking for your Finishing Moves

Let's take a closer look at the stats of this runeword. Compared to other claws, like Bartucs, Ghostsin runewords, or even some rare/magic claws, Mosaic offers minimal utility or damage at face value. However, the unique 25% non-consumption proc for finishing moves, unlocks the Assassin ability Martial Arts tree to a degree not possible without it, that is, the Assassin can now maintain fully stacked charge up ability procs which she can activate with her dragon finishing moves. Unlike other cookie cutter builds, the Mosaic Assassin is incredibly versatile in how you can build her. The versatility of her build tree also means there is less reliance on “core” items found in other builds. Enigma is nice but not necessary given she can teleport to foes with Dragonflight, and Infinity is not required as she has the most varied damage profile in the game (encompassing physical, lightning, fire, cold and even poison). In this guide we will focus on the most popular Lightning focussed variant, however, alternative gearing and skilling options will be provided.

Class Overview

The Assassin is a versatile and powerful Assassin build that excels in both single target damage, aoe damage (through her traps) crowd control and mobility. This build primarily focuses on the Shadow Disciplines and Martial arts skill trees, utilizing both elemental damage with physical damage sources. Traps can be used as an additional utility and damage tool.

Build Premise

This build leverages Mosaic to create a momentum based build that's extremely powerful when Mosaic's stacks are fully utilized and maintained during a farming run. This one runeword has multiplied the effectiveness of the Martial Arts (MA) tree and the inherent synergies found within it. The clunkiness of the original MA builds have been replaced by a fast paced and rewarding playstyle (with amazing visuals). However it should be noted that the charges have a limited duration and it is difficult to stack multiple stacks of different types (i.e. Phoenix Strike + Claws of Thunder). Therefore it is recommended that beginners focus on using Phoenix strike alone, and ensuring those stacks are maintained during a run, as this provides plenty of clear speed. Further optimisations by more experienced Assassins may warrant interweaving different charge procs, and ensuring they are proc'd before their durations elapse. For these reasons, we can consider the Mosaic Sin a high skill-ceiling build.

Skills

The core skills for the Mosaic Assassin are contained within the Martial Arts tree, with your support abilities contained within Shadow Disciplines.

Martial Arts Tree

The build suggestion here will be for the meta elemental based build using Phoenix Strike as your primary damage dealer. If you are opting into a different build or using some of our alternative suggestions, consider tinkering with the build depending on your focus and gear.

Tiger Strike (1): 1 Point prerequisite to your Charge up abilities.

Dragon Talon (1): 1 Point prerequisite to your Dragon finisher abilities.

Fist of Fire (1-20): A powerful Fire empowered attack, which is a primary damage synergizer with Phoenix strike. It increases the fire component of Phoenix strike damage and should be maxed, alongside Claws of Thunder and Blades of Ice where possible. This can be added to your charge cycle to add significant fire damage though is least prioritized when considering the three damage types.

Dragon Claw (1): A powerful double activation spell for your charge procs that will add very high damage and have the opportunity to double proc your Mosaic (retain charges). This is one of your primary finishers alongside Dragonflight and Dragontail.

Cobra Strike (1): A powerful sustain charge that can be added to your spell cycle to enable significant life and mana leech, use as required in combat as an additional sustain pool alongside potions and your item leech.

Claws of Thunder (20): Our most powerful elemental proc when fully optimized, and another primary synergy to Phoenix strike. This should be maxed as a priority in most situations, and provides interesting lightning skill additions to your attack that not only deals huge damage, but lights up the entire screen as you're in combat (Nova, Lightning, Charged Bolt).

Dragon Tail (1): A powerful single target immobilizer and DPS dealer, an optional finisher that can be cycled and tested. Particularly useful against bosses.

Blades of Ice (20): A useful Ice empowerment and primary synergizer to Phoenix strike offering a significant cold damage buffer. Theoretically another charge addition if you can manage the durations correctly.

Phoenix Strike (20): Phoenix strike will be our primary charge skill, has a triple faceted damage profile (on top of the raw physical) and is buffered by all its synergies. Maintaining Phoenix strike charges is your highest priority during a run, and is the skill that unlocks this build.

Dragon Flight (1): A powerful mobility and dps spell that can teleport you and proc current charges on a targeted enemy. This will be our primary mobility spell where teleport is unavailable or not used.

Shadow Disciplines Tree

Claw Mastery (1-20): Increases damage and attack rating with claw-class weapons as well as critical strike chance, particularly important for physical based builds. AR is important for all builds given elemental based builds still need to land their attacks.

Burst of Speed (1): Boosts attack and movement speed. This can be used to hit certain breakpoints where required. Enigma largely negates the need for additional FRW buffs, but BoS is particularly helpful where Enigma is not used.

Fade (1): Increases resistances and reduces curse durations. An ability that significantly increases your tankiness, use this where additional resistances and/or damage reduction is required. Particularly useful for difficult areas like Ubers.

Venom (1-20): Adds poison damage to your attacks. If you are trying to widen your already very wide damage profile, then feel free to add poison to the mix. This is mostly used by physical damage builds.

Shadow Master (1): Summons a powerful minion to aid you in battle. Shadow Master are similar to the Valkyrie for Amazons, and offers one powerful and versatile side-kick to help you in battle. The Shadow Master is great at providing an additional minion alongside your merc to damage soak and add negligible damage.

Bladeshield can be considered for some physical / venom based builds as poison will be applied when Bladeshield hits. However, the inherently low physical damage of Mosaic weapons mean that your Bladeshield will not be optimal.

Traps Tree (none)

Stat Allocation

• Strength: Enough to equip your desired gear.
• Dexterity: Enough to equip your claws
• Vitality: All remaining points should go here to increase your survivability.
• Energy: Not required; focus on items and charms with mana, mana regeneration or leech to meet your required mana sustain needs. This will depend on individual preferences. Mana after kills is a particularly useful mod on this build given the high kill volume / speed of Mosaic Sins.

Gear

Weapons

1. Dual Mosaic Runic Claws

Mosaic is the key to unlocking the build and doubling the proc preservation % is a necessary tool. To optimize this build fully, use Runic claws which have the fastest weapon speed. Look for additional mods to spawn on your base, particularly Phoenix strike synergizers like Blades of Ice, Claws of Thunder and Fire Fist. Alternatively look to save skill points by finding bases that have the ability so you can save skill points to invest elsewhere.

Armor

1. Enigma

While not necessary, Enigma is still one of the best, if not the best option. Teleport will help you maintain charges by shortening the time it takes to find new mobs to engage, where Dragon Flight is only useful in smaller spaces with denser mobs (to chain your ability). The other mods, are also powerful, and include an overlooked 45FRW which further aids your mobility and alleviates your need to use Burst of Speed. This means you can use Fade to offset the lack of resistances Enigma provides.

2. Treachery

Treachery is a fantastic low-cost option that provides good all-round defensive stats, and a high level Fade proc (less useful on an Assassin). The Increased attack speed is helpful and not found in other armor options. Use this in early leveling or until you can farm one of the other options.

3. Fortitude

Fortitude is a less considered option and mostly bumps physical damage, as well as providing some useful resistances and other mods (like chilling armor procs). If you are focussing on purely elemental damage like most Mosaic Sins, skip this armor.

4. Chains of Honor

The most powerful option to stack resistances, with a host of other useful mods. This is the best choice if Teleport from Enigma is not required (like for Ubers). Strength, Damage Reduction and Magic find are other benefits.

Helmet

1. Griffon's Eye Diadem

Griffon's Eye not only provides as huge damage increases to our lightning damage profile, it also provides +1 skills, and 25FCR which is the highest FCR amount you can find in the helm slot (all other helms being limited to 20). This is a fantastic option to pair with Enigma for faster teleporting, and can be considered the Best choice for our standard, Phoenix Strike / Teleport build with an Infinity-wielding Merc. This is traditionally socketed with a Lightning facet to promote damage further.

2. Crown of Ages

A very powerful defensive option that has one drawback, a massive strength requirement which will require significant stat investment to wield. This can be counterbalanced with a massive strength boost from Enigma, and/or a -15 requirement jewel with some other mod(s) ideally (or Hel rune). The most common jewels and runes socketed are (Ber (DR), Um (Res), -15req/+15all res, 15ias/15all res, Cham (CBF).

3. Guillaume's Face

A strong attack modifier booster that increases your Deadly Strike and Crushing Blow. While not boosting your elemental damage, this helmet can be very useful for the specialized task of boss or uber-killing given the useful CB mod, along with its other physical attack modifiers.

4. Shako

Shako is an easily attainable well-rounded helmet that can provide good general purpose use, although is not the best for any specialized task. Use as required to fill in the gap between upgrades and consider socketing with an Um, Ber or even just a perfect Gem to help with single resistance issues or add HP (Ruby)

Gloves

1. Trang Oul's Claws

Trang's is a fantastic caster glove, giving 20FCR and a substantial boost to Cold res (30). Unlike Its counterpart Magefist, it does not offer mana mods, so consider swapping out if mana is an issue and cold resistances aren't.

2. Magefist

20FCR, and mana regeneration. One of two gloves that offer FCR.

3. Rare/Craftied IAS Gloves

Consider a pair of IAS gloves if it is required to reach your desired IAS breakpoint. Useful additional mods will be +2 to Martial Arts, Life, Stats, Resistances. These may be harder to come across so consider using any 20ias glove as a temp (i.e. laying of hands).

Boots

1. Gore Riders

Much like Gface, Gores provides powerful attack modifiers which add to the strength of your abilities, particularly finishing moves for Boss-killing. Deadlystrike, Crushing Blow and Open Wounds are all useful mods.

2. Shadow Dancers

A high kick damage option also granting significant dexterity boost. A viable option intended for Kick-based Assassins by Blizzard.

3. Rare Tri Res

These boots may lack the kick damage of the other mentioned options but will cover up resistance weaknesses in the boot slot. These are ideal for a Phoenix strike based build that does not rely on kick damage. FHR, stats and replenish life are other useful mods you can find on rare boots.

4. Goblin Toes

An overlooked boot with the highest Crushing Blow % in the game. Great for Uber and Dclone.

Belt

1. Arachnid Mesh

A fantastic caster belt offering +1 Skills and 20FCR. A standard option with Enigma to hit desirable teleport speeds.

2. Thundergod's Vigor

A lightning sorb option used in specific areas like Ubers, where extra lightning resistances are required. Its relatively cheap cost makes this perfect to keep in the stash even if you use another primary belt.

3. Verdungo's Hearty Cord

A physical damage reduction option offering a good vitality bump as well for extra durability. Useful to cap out your DR along with Enigma (or COH) and Fade.

4. Nosferatu's Coil

Nos belt is a great option if you require IAS, and grants additional life leech. Alongside Goldwrap, these are the only belts that offer IAS in the game.

Rings

1. Bul-Kathos' Wedding Band

A great ring choice offering life leech, skills and life. This is the superior choice to SOJ which can still be considered if you are suffering heavily from mana issues.

2. Raven Frost

Cannot be Frozen is a must have somewhere in your gear. This is easiest to find in the ring slot, particularly since Ravenfrost offers a whole host of useful mods for a mosaic sin including AR, Dexterity, and Cold absorb.

Amulet

1. Mara's Kaleidoscope or a rare/crafted amulet with +skills and FCR

Maras offers a fantastic all round option with +2 skills, minor stats, and a huge bump to all resistances. Alternatively you could seek out a 2 skill FCR amulet with other mods if you want to hit a specific teleporting breakpoint.

2. Highlords is also viable, offering Deadlystrike, 1 skill and IAS.

Leveling Strategy

Leveling as a Mosaic Assassin is fairly straightforward. Start with Fire Blast.You shhold consider using traps for early leveling (like wake of fire), which will become your primary damage source early on. Begin working on your core skills and synergies, while simultaneously investing in Shadow Disciplines as needed. Once Lightning Sentry is available, it will become your main damage dealer. You can switch back to an MA build once you can use some of the gear which should alleviate early difficulties. Mana being one.

Mercenary Choice

An Act 2 Combat Mercenary is recommended for the Mosaic Assassin, as they provide excellent support and utility with their auras.

• Holy Freeze: This aura slows enemies around you, offering great crowd control and increased safety. This is a standard merc option for good reason, particularly in Hardcore.
• Prayer: A source of passive healing, synergizing well with your survivability-focused build.
• Might: This aura boosts your physical damage output and should be considered for physical focussed builds.
• Blessed Aim: this is an often overlooked merc variant that provides strong utility through improving your AR (on-hit chance). If you are struggling with hitting targets (especially in high ilvl areas like Terror Zones, then consider the Blessed Aim aura.

Equip your mercenary with gear that enhances their survivability, damage, and auras. The best choices are listed here. Check out our In-depth Merc Guide here.

Weapon

1. Infinity carries Conviction aura which amplifies the damage of every damage profile in your arsenal (including lowering enemy defenses, and removing some immunities). While not a must-have to traverse the game, it significantly increases your damage output and can help exponentially improve your clear speed.

2. Insight is a cheaper option that can be attained early on in your leveling. It eliminates any mana problems with Meditation aura which greatly improves smoothness and enjoyability when farming. It also provides good standalone weapon damage.

Helmet

1. Andariel's Visage is considered the best and most widely used Merc helmet due to its life-leech (which is integral to self-sustain on a merc), as well as IAS which increases damage (and lifeleech). The negative fire resistances should be offset to ensure your merc has maxed resistances in Hell. A ral rune is the cheaper option while a 15ias/30FR jewel is a more expensive option that can help your merc his the next IAS breakpoint with certain weapons (Eth Thresher, CV)
2. Vampire's Gaze is a great option for increased defensiveness, noting it lacks life leech. While many prefer this option, I have found the missing life leech to be annoying and requires you to micromanage your merc more closely.

Armor

1. Fortitude is the standard, and highest DPS option providing additional resistances as well. These should be sufficient to cap your resistances in hell so additional resistances from armors like Chains of Honor are not necessary.
2. In general high defense armors like Shaftstop or Stone runeword are also viable options but lack the damage that fortitude provides.

Gameplay Tips

Getting and keeping phoenix strike charges during a run is the most difficult aspect of this character, and requires the most practice. That is, developing an intuitive understanding of the timings of this character are important to optimizing her fully. Running out of stacks mid runs, reduces clear speed significantly as she is somewhat of a slow accelerator. Once you've perfected this, add in your other abilities. Choose one of Fade or Burst of Speed, and remember to prebuff (Venom, Battle Orders, Summon Shadow Master, Etc).

Endgame Content

The Mosaic Assassin performs well in endgame content, such as:

• Key farming: Farm the Countess, Summoner, and Nihlathak for keys, which are used to open the portals to the Uber Tristram event.
• Uber Tristram: Defeat Uber Mephisto, Uber Baal, and Uber Diablo to obtain a Hellfire Torch, which offers powerful bonuses.
• High-Level Areas (e.g., Chaos Sanctuary, Worldstone Keep): Farm these areas for experience, runes, and unique items.
• Chaos or Baal runs: in Players 8
• Terror Zones
• Cow Levels

Conclusion

With this comprehensive guide, you should now be equipped with the knowledge necessary to master the Mosaic Assassin. Keep in mind that this build is versatile and can adapt to various playstyles, so don't hesitate to experiment and discover what works best for you. You will find out quickly that this is one of the most powerful current builds in the game. If you're looking to get ahead quickly, check out the RPG Gear Shop for all price ranges, across all servers (Ladder or Non-Ladder, including Hardcore).

Related Guides

Ultimate Mercenary Guide | D2R Rune Farming Guide | 4 Socket Monarch Farming Guide